/*
 * ====================================================================
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *   http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
 * information on the Apache Software Foundation, please see
 * <http://www.apache.org/>.
 *
 */

package com.feilong.lib.org.apache.http.impl;

import java.util.Locale;

import com.feilong.lib.org.apache.http.HttpStatus;
import com.feilong.lib.org.apache.http.ReasonPhraseCatalog;
import com.feilong.lib.org.apache.http.annotation.Contract;
import com.feilong.lib.org.apache.http.annotation.ThreadingBehavior;
import com.feilong.lib.org.apache.http.util.Args;

/**
 * English reason phrases for HTTP status codes.
 * All status codes defined in RFC1945 (HTTP/1.0), RFC2616 (HTTP/1.1), and
 * RFC2518 (WebDAV) are supported.
 *
 * @since 4.0
 */
@Contract(threading = ThreadingBehavior.IMMUTABLE)
public class EnglishReasonPhraseCatalog implements ReasonPhraseCatalog{

    // static array with english reason phrases defined below

    /**
     * The default instance of this catalog.
     * This catalog is thread safe, so there typically
     * is no need to create other instances.
     */
    public final static EnglishReasonPhraseCatalog INSTANCE = new EnglishReasonPhraseCatalog();

    /**
     * Restricted default constructor, for derived classes.
     * If you need an instance of this class, use {@link #INSTANCE INSTANCE}.
     */
    protected EnglishReasonPhraseCatalog(){
        // no body
    }

    /**
     * Obtains the reason phrase for a status code.
     *
     * @param status
     *            the status code, in the range 100-599
     * @param loc
     *            ignored
     *
     * @return the reason phrase, or {@code null}
     */
    @Override
    public String getReason(final int status,final Locale loc){
        Args.check(status >= 100 && status < 600, "Unknown category for status code " + status);
        final int category = status / 100;
        final int subcode = status - 100 * category;

        String reason = null;
        if (REASON_PHRASES[category].length > subcode){
            reason = REASON_PHRASES[category][subcode];
        }

        return reason;
    }

    /** Reason phrases lookup table. */
    private static final String[][] REASON_PHRASES = new String[][] {
                                                                      null,
                                                                      new String[3], // 1xx
                                                                      new String[8], // 2xx
                                                                      new String[8], // 3xx
                                                                      new String[30], // 4xx
                                                                      new String[8] // 5xx
    };

    /**
     * Stores the given reason phrase, by status code.
     * Helper method to initialize the static lookup table.
     *
     * @param status
     *            the status code for which to define the phrase
     * @param reason
     *            the reason phrase for this status code
     */
    private static void setReason(final int status,final String reason){
        final int category = status / 100;
        final int subcode = status - 100 * category;
        REASON_PHRASES[category][subcode] = reason;
    }

    // ----------------------------------------------------- Static Initializer

    /** Set up status code to "reason phrase" map. */
    static{
        // HTTP 1.0 Server status codes -- see RFC 1945
        setReason(HttpStatus.SC_OK, "OK");
        setReason(HttpStatus.SC_CREATED, "Created");
        setReason(HttpStatus.SC_ACCEPTED, "Accepted");
        setReason(HttpStatus.SC_NO_CONTENT, "No Content");
        setReason(HttpStatus.SC_MOVED_PERMANENTLY, "Moved Permanently");
        setReason(HttpStatus.SC_MOVED_TEMPORARILY, "Moved Temporarily");
        setReason(HttpStatus.SC_NOT_MODIFIED, "Not Modified");
        setReason(HttpStatus.SC_BAD_REQUEST, "Bad Request");
        setReason(HttpStatus.SC_UNAUTHORIZED, "Unauthorized");
        setReason(HttpStatus.SC_FORBIDDEN, "Forbidden");
        setReason(HttpStatus.SC_NOT_FOUND, "Not Found");
        setReason(HttpStatus.SC_TOO_MANY_REQUESTS, "Too Many Requests");
        setReason(HttpStatus.SC_INTERNAL_SERVER_ERROR, "Internal Server Error");
        setReason(HttpStatus.SC_NOT_IMPLEMENTED, "Not Implemented");
        setReason(HttpStatus.SC_BAD_GATEWAY, "Bad Gateway");
        setReason(HttpStatus.SC_SERVICE_UNAVAILABLE, "Service Unavailable");

        // HTTP 1.1 Server status codes -- see RFC 2048
        setReason(HttpStatus.SC_CONTINUE, "Continue");
        setReason(HttpStatus.SC_TEMPORARY_REDIRECT, "Temporary Redirect");
        setReason(HttpStatus.SC_METHOD_NOT_ALLOWED, "Method Not Allowed");
        setReason(HttpStatus.SC_CONFLICT, "Conflict");
        setReason(HttpStatus.SC_PRECONDITION_FAILED, "Precondition Failed");
        setReason(HttpStatus.SC_REQUEST_TOO_LONG, "Request Too Long");
        setReason(HttpStatus.SC_REQUEST_URI_TOO_LONG, "Request-URI Too Long");
        setReason(HttpStatus.SC_UNSUPPORTED_MEDIA_TYPE, "Unsupported Media Type");
        setReason(HttpStatus.SC_MULTIPLE_CHOICES, "Multiple Choices");
        setReason(HttpStatus.SC_SEE_OTHER, "See Other");
        setReason(HttpStatus.SC_USE_PROXY, "Use Proxy");
        setReason(HttpStatus.SC_PAYMENT_REQUIRED, "Payment Required");
        setReason(HttpStatus.SC_NOT_ACCEPTABLE, "Not Acceptable");
        setReason(HttpStatus.SC_PROXY_AUTHENTICATION_REQUIRED, "Proxy Authentication Required");
        setReason(HttpStatus.SC_REQUEST_TIMEOUT, "Request Timeout");

        setReason(HttpStatus.SC_SWITCHING_PROTOCOLS, "Switching Protocols");
        setReason(HttpStatus.SC_NON_AUTHORITATIVE_INFORMATION, "Non Authoritative Information");
        setReason(HttpStatus.SC_RESET_CONTENT, "Reset Content");
        setReason(HttpStatus.SC_PARTIAL_CONTENT, "Partial Content");
        setReason(HttpStatus.SC_GATEWAY_TIMEOUT, "Gateway Timeout");
        setReason(HttpStatus.SC_HTTP_VERSION_NOT_SUPPORTED, "Http Version Not Supported");
        setReason(HttpStatus.SC_GONE, "Gone");
        setReason(HttpStatus.SC_LENGTH_REQUIRED, "Length Required");
        setReason(HttpStatus.SC_REQUESTED_RANGE_NOT_SATISFIABLE, "Requested Range Not Satisfiable");
        setReason(HttpStatus.SC_EXPECTATION_FAILED, "Expectation Failed");

        // WebDAV Server-specific status codes
        setReason(HttpStatus.SC_PROCESSING, "Processing");
        setReason(HttpStatus.SC_MULTI_STATUS, "Multi-Status");
        setReason(HttpStatus.SC_UNPROCESSABLE_ENTITY, "Unprocessable Entity");
        setReason(HttpStatus.SC_INSUFFICIENT_SPACE_ON_RESOURCE, "Insufficient Space On Resource");
        setReason(HttpStatus.SC_METHOD_FAILURE, "Method Failure");
        setReason(HttpStatus.SC_LOCKED, "Locked");
        setReason(HttpStatus.SC_INSUFFICIENT_STORAGE, "Insufficient Storage");
        setReason(HttpStatus.SC_FAILED_DEPENDENCY, "Failed Dependency");
    }

}
